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SMSL SU-9 Balanced DAC Review

Shoaibexpert

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@Shoaibexpert - I have been thinking of your crackling sound and it reminded of something I had a while back with Roon. It failed to work out of the blue, but worked fine on a different laptop. It turned out Nero has a Wifi transfer app that interfered with the same port Roon was using. I uninstalled the Nero app and Roon started working fine again. I think you may want to test this by connecting a different laptop to the DAC and see if it will do the same, if it doesn't do it in a different machine, then the chances are there is software on your machine that is not playing nice with the DAC. Go to your startup and disable it (if it is one of those that start as you boot up. All the best.
Thanks. I just got rid of the noisy fan utilizing laptop and got a Bluesound Node (hard wired to LAN switch) and am using it as a Roon end point as a digital transport ie optical into the SMSL SU-9 (which was recently returned after reflash from US). Must say in my setup, switching to the new set-up seemed to make the noise floor lower making my music smoother at the top end with sort of a more easy listening experience. I am clocking the optical signal by the IFI SPDIF IPurifier 2 (connected by a Linear PSU) as those happened to be lying around. As with anything audio perception related, this could all be placebo and YMMV.

As for the crackles, they are gone and it's a joy to use the SU-9 remote as the Node remote to control Roon (by pressing say B button to switch device)
20210814_123727.jpg
 

Esss

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Great - I also connected the node 2i to the SMSL coaxial. It works a charm, especially with Deezer which it sends bit-perfect. Tidal is only first unfold as it cannot unfold coaxial signals, but still, 96kHz is awesome. Eventually I split them up into two different setups. Enjoy the music.
 

Shoaibexpert

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Great - I also connected the node 2i to the SMSL coaxial. It works a charm, especially with Deezer which it sends bit-perfect. Tidal is only first unfold as it cannot unfold coaxial signals, but still, 96kHz is awesome. Eventually I split them up into two different setups. Enjoy the music.
I think the Node can work as a full MQA decoder. The 96Khz might be the fully unfolded stream reaching your DAC.
 

Esss

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Coaxial digital out doesn't send fully unfolded signals. Test it out, Kenny Burrell Midnight Blue (2012 remaster) album is 192kHz.
 

Shoaibexpert

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Coaxial digital out doesn't send fully unfolded signals. Test it out, Kenny Burrell Midnight Blue (2012 remaster) album is 192kHz.
Strange. I also noticed the same. The Roon path clearly shows that the Node is unfolding thwbsognal to 192KHz but my SU-9 shows 96Khz. Don't know what's the gap here. FWIW I am noticing that the Optical out from the Node sounds more cleaner and impactful in my setup and for some reason I can't get anything beyond 96KHz even if I upsample the signal. But for Coax, of I upsample, it does throw out 192KHz
Screenshot_20210815-131313_Roon.jpg
 

Shoaibexpert

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Great - I also connected the node 2i to the SMSL coaxial. It works a charm, especially with Deezer which it sends bit-perfect. Tidal is only first unfold as it cannot unfold coaxial signals, but still, 96kHz is awesome. Eventually I split them up into two different setups. Enjoy the music.
Btw, there is also a theory that the MQA filtering on non-MQA content as applied by the Node or other MQA players also helps with the sound quality (maybe just hear say w/o any scientific basis). Anyways, my R7s have never sounded so clean and impactful...
 

Esss

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Interesting, I didn't know about the filtering. But about the Node coax sounding better, It may just be placebo but I also heard it. I was quite certain when the SMSL is fed coax by the Node it sounded better. Maybe those folks with measuring gadgetry can check this out and see if there are any measurable differences. In my case, it was specifically Deezer, bearing in mind that there is no exclusive mode on Deezer. I am not sure if you have heard this, when you listen to Tidal without exclusive vs with, there is an audible difference to the sound. Very similar to that.
 

Shoaibexpert

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Interesting, I didn't know about the filtering. But about the Node coax sounding better, It may just be placebo but I also heard it. I was quite certain when the SMSL is fed coax by the Node it sounded better. Maybe those folks with measuring gadgetry can check this out and see if there are any measurable differences. In my case, it was specifically Deezer, bearing in mind that there is no exclusive mode on Deezer. I am not sure if you have heard this, when you listen to Tidal without exclusive vs with, there is an audible difference to the sound. Very similar to that.
Actually, I preferred optical from the Node. Yes, Tidal in exclusive mode via USB is cleaner than the other mode...but Ive now moved to Optical so doesn't matter.
 

reddie.k

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Hi,

Just received the SMSL SU-9.

Anyone knows which volume value corresponds to 2.8 Volts output (balanced) in the Pre variable mode?

My Yamaha A-S2000 amplifier accepts only 2.8 V maximum voltage for the balanced inputs.

Any help is appreciated.

Konstantinos
 

reddie.k

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Hi,

Just received the SMSL SU-9.

Anyone knows which volume value corresponds to 2.8 Volts output (balanced) in the Pre variable mode?

My Yamaha A-S2000 amplifier accepts only 2.8 V maximum voltage for the balanced inputs.

Any help is appreciated.

Konstantinos

In case it helps someone: "the SU-9 can adjust the output level to 2.82V (at volume 87), 2.67V (at volume 86)"

The answer is by shenzhenaudio.

Edit: The fixed output levels: "For the ouputs, 2V for RCA and XLR is 4V."
 
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Sanlitun

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In case it helps someone: "the SU-9 can adjust the output level to 2.82V (at volume 87), 2.67V (at volume 86)"

The answer is by shenzhenaudio.

Edit: The fixed output levels: "For the ouputs, 2V for RCA and XLR is 4V."

I received mine yesterday and I am quite confused about this. Amir says that setting the volume to 94 produces 4v from the balanced outputs. But if I set the output to fixed it defaults to 99 and is certainly louder than variable volume at 94. In fact I felt it was clipping with a THX 789 on fixed volume. The signal is certainly hot enough to lose details.

So far a bit of a mixed bag for me.
 

reddie.k

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I received mine yesterday and I am quite confused about this. Amir says that setting the volume to 94 produces 4v from the balanced outputs. But if I set the output to fixed it defaults to 99 and is certainly louder than variable volume at 94. In fact I felt it was clipping with a THX 789 on fixed volume. The signal is certainly hot enough to lose details.

So far a bit of a mixed bag for me.

Maybe you will find the answer here: http://www.referencedesigner.com/rfcal/cal_04.php

There is a difference between the rms voltage and the maximum voltage. And each value can be calculated from the other.

Shenzhenaudio also recommended to turn the amplifier volume all the way up and start the Preamp from 0 and up. The sound seems quite good like this.
 

Shoaibexpert

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In terms of the new Serial Numbers of the SU-9, has anyone verified yet that the S. Nos starting with 6 have in fact been flashed/corrected for the 3rd harmonic issue?
 

Sanlitun

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Anyone have a favorite filter to use with this? I started with Slow Minimum but after a while felt it was too soft and went to the default Fast Linear. After experimenting Slow Linear seems to be the most natural via my amp.
 
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mario_rouge

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in the end I got a su9. it is connected to a da9 with balanced cables. I have a bit of a dull sound. I don't know if it depends on the burn in. what experience do you have? what settings do you use? i use jriver. with a Dragonfly red the sound is less detailed but more dynamic and less blurred.
 

Raikon_N

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So if I understand it correctly, the issue happens when using the unit in pre-amp mode? So fixed-volume mode should be normally ok? TIA
I apologize if I misunderstood it.

I reached out to the AliExpress store where I bought my SU-9, and they said I need to pay for the back and forth international shipping fee. So I am reluctant to do it at the moment.
 

reddie.k

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in the end I got a su9. it is connected to a da9 with balanced cables. I have a bit of a dull sound. I don't know if it depends on the burn in. what experience do you have? what settings do you use? i use jriver. with a Dragonfly red the sound is less detailed but more dynamic and less blurred.

Maybe try this:

"There are various tuning presets available with the DA-9, but they are just frequency response tunings. Interestingly, the DA-9 has an SDB mode, and it sounded significantly better than most of the other tuning filters.

It seems that the SDB mode implements a version of the Fletcher-Munsen curve compensation that seems to compensate for the perceived lack of bass and treble at lower volumes, while retaining a perception of neutrality, giving a clear sense of midrange presence."


From this review: https://headfonics.com/smsl-da-9-review/
 

mario_rouge

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Maybe try this:

"There are various tuning presets available with the DA-9, but they are just frequency response tunings. Interestingly, the DA-9 has an SDB mode, and it sounded significantly better than most of the other tuning filters.

It seems that the SDB mode implements a version of the Fletcher-Munsen curve compensation that seems to compensate for the perceived lack of bass and treble at lower volumes, while retaining a perception of neutrality, giving a clear sense of midrange presence."


From this review: https://headfonics.com/smsl-da-9-review/
i tried but the sound is still flat
 
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